Enable networking and console over the USB port

That one is much more friendly than the UART0 pin header.

Change-Id: I76affd2803eb2f18911eb71cbdfc1ffd6bf4fd76
diff --git a/board/czechlight/common/kconfig b/board/czechlight/common/kconfig
new file mode 100644
index 0000000..5004b78
--- /dev/null
+++ b/board/czechlight/common/kconfig
@@ -0,0 +1,3 @@
+# CONFIG_USB_ZERO is not set
+CONFIG_USB_CDC_COMPOSITE=m
+# CONFIG_USB_G_NOKIA is not set
diff --git a/board/czechlight/common/overlay/etc/modules-load.d/usb-serial-gadget.conf b/board/czechlight/common/overlay/etc/modules-load.d/usb-serial-gadget.conf
new file mode 100644
index 0000000..41c481d
--- /dev/null
+++ b/board/czechlight/common/overlay/etc/modules-load.d/usb-serial-gadget.conf
@@ -0,0 +1,2 @@
+# composite module for serial console and Ethernet over the miniUSB port
+g_cdc
diff --git a/board/czechlight/common/overlay/etc/systemd/network/30-usbnet-apipa.network b/board/czechlight/common/overlay/etc/systemd/network/30-usbnet-apipa.network
new file mode 100644
index 0000000..807dcc4
--- /dev/null
+++ b/board/czechlight/common/overlay/etc/systemd/network/30-usbnet-apipa.network
@@ -0,0 +1,6 @@
+[Match]
+Name=usb0
+
+[Network]
+Description=miniUSB console
+LinkLocalAddressing=yes
diff --git a/board/czechlight/common/overlay/etc/systemd/system/serial-getty@ttyGS0.service b/board/czechlight/common/overlay/etc/systemd/system/serial-getty@ttyGS0.service
new file mode 120000
index 0000000..252308a
--- /dev/null
+++ b/board/czechlight/common/overlay/etc/systemd/system/serial-getty@ttyGS0.service
@@ -0,0 +1 @@
+/lib/systemd/system/serial-getty@.service
\ No newline at end of file